SYSTEM_ALERT_WINDOW Permission is being automatically handled if you ever pass it along other permissions ;) .

And Finally Let The Library Do The Job For You. in Style.

Notice

You still can use the library to explain why you used the permission in your app, the library will never try ask the permission if
Android is smaller than M, it will just do like any Intro library does. as you can see in Nexus 7 & Nexus 10 screens running Android L,
request button is hidden ;).